They go on in any position
CK5
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L18 8.1L swap resource thread
- Thread starter Larry
- Start date
pulling my 02 8.1 in the morning . . got a master fel-pro kit for gaskets and head bolts . anything else to do and or watch for on my long block swap ?
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Doing valve seals and borrowed my buddys proform spring compressor and it is only good for american threads
So i went to my metal pile of cuts and found a chunk of solid round bar and whipped up a new center pin .
8mmx1.00 pitch for our studs . Works like a charm .
So i went to my metal pile of cuts and found a chunk of solid round bar and whipped up a new center pin .
8mmx1.00 pitch for our studs . Works like a charm .
anyone have the info on rocker arm adjustment specs ? first time doing one on a 8.1 and wasn't sure is old style or newer ls style tight and done .
I believe is tighten dowand done. I could not find a procedure, only a torque spec 26ft pd
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Just 8.1 stuff . . . Stuff is all over the shop right now 
If you own a 8.1 you know this battle . Or any late model with smaller size hardware that always brakes .
exhaust manifold studs?
Yep. Stupid they are so small. I can hear on mine one either backed off or broke.
Here's the picture from my build thread:
You can see that 8 or 9 broke off and at least 4 came out whole. It looks like I pulled 5 by welding nuts (obviously multiple attempts), at least one with an extractor, then a couple by drilling into the head a bit to remove the outermost thread (where corrosion is the worst.) Finally drilled one or two all of the way, working from small bits to where I could eventually run a tap. Nothing like a 10-minute job taking a couple of days. I can't imagine doing that in the engine bay.
So, is there a fix for this, like drilling and tapping bigger? Even with stainless hardware, the head will likely still corrode it in, but if you had a really good stud/nut that would still come apart, you wouldn't really care that the stud is stuck in the head. From my 3800 days, that hardware seemingly always came apart and could be reused.
You can see that 8 or 9 broke off and at least 4 came out whole. It looks like I pulled 5 by welding nuts (obviously multiple attempts), at least one with an extractor, then a couple by drilling into the head a bit to remove the outermost thread (where corrosion is the worst.) Finally drilled one or two all of the way, working from small bits to where I could eventually run a tap. Nothing like a 10-minute job taking a couple of days. I can't imagine doing that in the engine bay.
So, is there a fix for this, like drilling and tapping bigger? Even with stainless hardware, the head will likely still corrode it in, but if you had a really good stud/nut that would still come apart, you wouldn't really care that the stud is stuck in the head. From my 3800 days, that hardware seemingly always came apart and could be reused.
Short of drilling out the head to put the same size hardware the earlier big blocks used there isn’t a simple fix.
I was out in a trip and head a wispy leak on the driver side manifold and with nothing more than a a 3/8” ratchet I snapped a stud off. Keep in mind mine rarely gets driven in snow and isn’t exposed to the moisture you guys back east have. It’s just too small.
I was out in a trip and head a wispy leak on the driver side manifold and with nothing more than a a 3/8” ratchet I snapped a stud off. Keep in mind mine rarely gets driven in snow and isn’t exposed to the moisture you guys back east have. It’s just too small.
I think I would swap them for ARP stainless before they corrode. It's stronger and corrosion resistant and can take the heat. Regular SS is weak and galls with any heat.
Do you know of any success stories?
I agree that HW store stainless would not be a good solution. I was thinking of getting some (known good) factory studs from another application. The factory 8.1L studs are likely some form of SS.
It definitely doesn't appear that way from the light colored plating and then the horrible corrosion in the pictures, SS that can take heat and not gall is quite expensive. They make grades well above even the ARP stainless that can take more heat, like Inconel 625 or 718, but they are quite expensive.
There are over 150 kinds of SS - basically any steel with Chromium and Nickel, but looking at the pictures, they do resemble the aluminum or zinc-coated mild steel fasteners so common on GM vehicles. Of course, on any engine 20+ years old, who knows what's been swapped.
Like I was saying about the 3800s. I could unbolt exhaust manifolds from 200,000 mile engines and re-use the hardware. It may even be the same thread. I should see if I still have some.
Like I was saying about the 3800s. I could unbolt exhaust manifolds from 200,000 mile engines and re-use the hardware. It may even be the same thread. I should see if I still have some.
Same here, I ended up drilling out a few of them. Re-tapping the holes.
I’m thinking of if I keep having troubles with them of using copper nuts. No way for them to become one with the stud or manifold for that matter. I realize that I will be constantly retightening them.
I’m thinking of if I keep having troubles with them of using copper nuts. No way for them to become one with the stud or manifold for that matter. I realize that I will be constantly retightening them.
That looks painful! I can here the dissatisfaction!
not sure if this has been posted up yet . but i got it from the 8.1 fb group i am on .
Hmm. This is the first I've heard of this stud issue.
I guess I'll start soaking the studs with Fluid Film now, while it's still in the running donor truck. Maybe if I constantly soak them and give them some heat cycles, it won't be an issue later on.
I guess I'll start soaking the studs with Fluid Film now, while it's still in the running donor truck. Maybe if I constantly soak them and give them some heat cycles, it won't be an issue later on.
Do what you can. Just don’t be surprised if you snap a couple. Like I said I was able to break one that had backed off a little by going a little past snug with a 3/8” ratchet handle. No power tools, just my big bear paw on it.
If I ever ran into the GM powetrain engineer that thought the stupid little studs were a good idea, I’d probably beat him senseless and shove the broken studs up under his fingernails.
